Control for hot-water systems



R. H. SHADRICK CONTROL FOR HOT WATER SYSTEMS Filed Aug. 12, 1927 2 Sheets-Sheet l April 14, 1931.

April 14, 1931. R. H. sHADRlcK CONTROL FOR HOT WATER SYSTEMS Filed Aug. 12, 1927 2 Sheets-Sheet 2 Patented Apr-. 14, 1931 UNITED STATES PATENT OFFICE RICHARD H. SHADRICK, OF MINNEAPOLIS, MINNESOTA,v ASBIGNOB, BY M ESNE AS- SIGNMECLI'TS,y TO vMILWAUKEE GAS SPECIALTY COMPANY, OF MILWAUKEE, WIS- cONsIN, A CORPORATION CONTROL FOR HOT-WATER SYSTEMS i pplioation tiled August 19, 1927. Serial No. 812.498.

This linvention relates to mechanisms -for controlling the burners of hot water heating systems, and theprimary object is to provide means of a novel, etlicienty and practlcal nature for manually lighting and extinguishing vthe burner, from a point remote therefrom, together with means of a novel character yfor automatically extinguishing the burner, after it has firstbeen manually lighted, and at a time when a predetermined amount of water has been heated, thereby insuring the extinguishment'of the burner in case the householder or operator should forget to manually extinguish the burner. Further and more specific objects will be disclosed in the course of the following specification, reference being had to the accompanying drawings, wherein:

Fig. 1 is lan elevationl of the major portion of the water heating system to which my device is connected, and illustrates, in sectional elevation, the parts of the house in which the system isinstalled.

Fig. 2 is an enlarged detail view of one of lm improved operating stations, parts of whic 1 are shown in section.

Fig. 3 is an enlarged detail sectional view through' one of the adjustable weight stops.

Fig. 4 is an enlarged detail elevation of the tank cut-olf unit.

Fig. 5 is a sectional elevation on the line 55 in Fig. 4.

Fig. 6 is a view similar to the lower portion of Fio. 5, but showing the cut-off as approac ing its automatic self-locked condition.

Fig. 7 1s a detail section on the line 7-7 in Fig. 5.

Referring to the drawings more-particu;A

larly and by reference characters A designates a water tank which is connected up, in a well known manner, with the coil B of a heater C by means of pipes 'D and E. The heater is provided with the usual burner F supplied with gas by a pipe G. H designates -the partition or wall of a first floor room,

such as a kitchen, while I designates the wall or partition of a second floor room, such as a bath room. The sinks and other fixtures (not shown) in such rooms, to which hot water is conducted, are connected by suitable pipes With the hot water system, as at J, while the cold water supply pipe to theof common and well known construction, and

is shown in my Patent No. 1,563,532 issued for Heater control, and is also shown in ymy copending application Ser.No. 150,299, iled November 23, 1926, for Control mechanism, as a -division ofthe application (Ser. No. 734,180) resulting in said Patent No. 1,563,532. It may here be noted that the present invention 1s specifically for improvements upon the control system shown in the aforesaid patent and application.

At a convenient and suitable place in the fuel supply pipe G, I place or insert a valve "L, to control the ow of gas in the ipe G to the burner F. The -valve is pre erably placed in a vertical section of the pipe G, and near the heater, so that it can be brackf eted thereto as at 8, by a bracket 9, which is also rigid with the valve L. A pilot tube 10 extends from the intake side of the valve into the heater casing C so as to always be in a li htin position with respect to the burner T e member 9 is further provided with a lever arm 10a, which when permitted to drop down under the pull of a spring 11, permits the valve L to close, but, when pulled up, by a chain or cable 12, will cause the valve to Open. The specific construction of the valve actuator unit 8-11, is not here shown in detail, as such will form the subject matter of a separate application. It is no doubt sufficient to state that the actuator unit shown in my former patent is a substane tial equivalent and that the arm 8, there shown, corresponds to the present arm 10a. In either event the arm permits the valve to close, when lowered, and causes it to open, when raised, and, as far as the present invention is concerned, any kind of an actuator, which has a member adapted to o en when actuated by a pull chain, and w ich will close or permit the valve to close, when the chain is released, may be used.

One end of the chain 12 is secured to the lever arm 10a of the actuator, which, as a unit may be designated by the letter M, and from there passes over amovable pulley 13,

its other or opposite end being secured to a lever 14 of a tank-cut-o unit N. This unit isheld in place, in any selected position on the tank A, by a pair of straps or wires 15, which are secured about the tank and which are preferably provided withvelastic spring sections 16.

The tank cut-off unit N comprises a casing 17, which is preferably V-shaped in cross section (see Fig. 7), and is secured with its open side against the tank so that the interior thereof will be directly subjected to the temperature of the tank. The upper end of the casing 17 is substantially closed by a leaf 18 so as to prevent too much updraft through it, but a restricted passage is provided near the tank surface, as at 19 (see Fig. 5), so that there will be a slight circulation of air immediately adjacent the tank surface.

In the upper end of the casing 17 is a bolt 20, having a sleeve 21 and a nut 22, between the latter two elements of which is irmly secured the upper end of a strip of thermostaticy metal '23. This strip is of the well known bi-metal class, comprising two kinds ot metal havinr dill'ferent co-ellicients of' expansion, whereby it is caused to bend or be distorted upon bein subjected to variations in temperature. Vhen comparatively cool the strip is straight, but when heated will bend toward the tank as shown by the dotted lines in Fig. 5.

Co-operating with the lower or movable end the thermal strip 23 is a latch or dog 24 having an end tooth 25 for engagement under the end of the strip. This latch operates through a slot 26 in the front wall of the casing 17, and is pivotally secured by a pin 27, carried by the side walls of the casing. The outer end of the latch is slightly heavier than the inner end, so that when it is released from the thermal strip it will drop to the position shown by dotted lines in Fig. 6, Where it stops at the lower end of the slot 26. The latch 24 is further provided with a notch 28 adapted to be engaged by a lug 29 of the lever 14.

The members 14 and 24 are normally in the positions shown in full lines in Figs. 1, 4, 5 and 7, and remain so as long as the hot water level in the tank is above the point of the cut-oft' device N. As the volume of hot water increases, however, this level lowers and as the tank surface adjacent the cut-ott' becomes heated by the water the thermal strip will also become heated, and will move to release the latch 24, and as this is done the notch 28 releases the lug 29, permitting the lever 14 to be pulled or raised to the dotted line position shown in Fig. 5. lVhen the lever 14 is later released it drops down, aided by a spring 30, the lug 29 re-engages the notch 28 and the latch 24 is restored to its initial position. vIf the thermal strip 23 has cooled, in the mean time, so as also to be restored to its initial position, the tooth 25 will snap under it, as indicated in Fig. 6, the strip 23 flexing enough for this purpose. As the tooth 25 exerts some pressure upward ly against the strip 23 the resistance might frequently be suiiicientto prevent the strip from snapping out to release the catch, i. e., instead ot' the lower end of the strip moving oit of the latch its middle portion would tend to bow in the other direction or away from the tank. To overcome this difficulty I provide an L-shaped piece of metal 31 adjacent to the strip. llh-is piece has its upper end secured, by the bolt 20, between the sleeve 21 and the strip proper, while its lower end terminates in a horizontal leg which abuts against the t'ront wall of the casing and has a notch 32 which permits freedom of movement to the lever 14. The member 31 is ri id at all times, it not temperature influence and, as it backs up substantially the entire strip 23 it will be seen that the latter cannot bow, but can respond to an increase of temperature only by moving its lower end away from the latch 24 to release the same. It may here be noted that the strip 23 may be adjusted so as to el'ectively respond to any predetermined degree of temperature desired, by a set screw 32 which screws in the casing 17 and operates through a hole 33, in the member 31, so as to contact with the thermal metal, and is preferably provided with a lock nut 34.

It will now be seen that when the pulley 13 is raised it will not affect the lever 14 (when the tank A is cold), but will raise only the lever 10a of the valve actuator .M. )Vhen this is done the burner F of the heater C is ignited, and as the coils B become heated, hot water will start to accumulate in the upper part of the tank. lfVhen a sufficient amount of hot water is heated the pulley 13 lnay be lowered, by releasing the pull chain in one of the rooms upstairs, but if this is not done within a reasonable time, or if the 0ccupant should leave the building and forget the heater, no harm will be done, because as soon as the predetermined amount of water is heated, the lever 14 will be released, and under the action of the spring 11 will move up giving enough slack to the chain 12 so that the actuator arm 10a may drop, permitting the valve to close. ljVhen hot watier is then drawn off or if the tank merely cools of itself, the thermal strip is restored to its original latch-hold ing position. Lowering of the pulley 13 will now permit the tank cut-olil to return to its initial condition (under the influence of the spring 30 and the weight of the lever 14), after which the entire device is again in readiness to be operated to light the heater. It may be noted that with this hookup it is impossible to heat more than a certain amount of hot water, regardles of how roften the device may be actuated from up- \rooms in the building as may be provided with control stations. In the present instance two stations O and P may beconveniently considered as being arranged in the kitchen and bath room respectively, of a dwelling. One of these stations is shown in detail in 'Fi 2, and may be described as follows: A wa l plate 35, similar to an electric y light switch plate, is secured upon the wall at any suitable place such as above a sink, and is 'provided with a tu-bular member 36 which extends in through a hole in the plaster and lath so that it will terminate in the hollow part of the wall, and is there turned down in a goose neck portion 37, so as to form a curved bearing for the pull chain 38. The member 36 is secured to the plate 35 by nuts 39, and at an intermediate oint between its ends is provided with a ho e 40 in which is arranged a ball 41. This ball is held in place, and is yieldingly pressed down against the chain 38 by a sprino 42, which has one end rigidly secured to the member 36, as at 43, while its other end is provided with a finger lift hook 44. The tension ofthe spring-42 against the ball 41 is such that it will normally retain the chain in its drawn position (as against the pull by the springll) but a greater pull than exerted by the spring 11 will cause the chain to slip under the ball.

The chain 38 passes over suitable pulleys 45, and its ends are respectively threaded through the stations O and P, being provided with terminal members 46 and 47, which serve as gripping members and also actas stops to limit the retraction of the chain ends through the stations. The chain 38 also passes under a pulley48 which is connected to the pulley 13 by a tie link 49. A pair of weights 50 are carried by the chain and while serving to take up the slack in the chain, they also assist the spring 11 to lower the chains when released at the stations; and also act as stops to prevent the upper chain to cause too hard a pull on the lower chain and thus causing any damage to the units N or M. Thus when the chain 38 is pulled through the station O, the left Weight 50 (as seen in Fig. 'l stops aga-inst a plate 51 as soon as the pu l on the chain 12 is suiiicient to operate the valve actuator M, and, in a similar manner the right weight 50 will stop against the adjacent pulley 45. The weights are preferably cored, as shown in Fig. 3, and are secured by sub antially V-shaped wires 52 which may rst be secured in any desired link of the chain, after which the weight is slipped down upon it.

It will now be seen that when the hand piece 46 is pulled, at station O, until the left Weight 50 meets the stop 51, the chain 38 will raise the twin pulleys 13 and 48 until the arm'lOa is lifted to light the burner. By liftin the hook 44, at station O, the burner wil be extinguished, or, as previously explained, if

this is forgotten then the burner will be auto.- 4

matically extinguished, by the action of the cut-out N, as soon as a predeterminedamount of water is heated. It will of course be understood that to vary this volume of hot water, it is only necessary to move the unit N up or down on the tank and correspondingly shorten or lengthen the chain 12.

The operation of the device is the same from station P. It is also possible to light the heater from one station and manually extinguish it from the other station, as follows: As shown in Fig. 1, the heater has been lighted from station O. To extinguish it from station P, the operator pulls the terminal member 47 until the chain has been drawn back through station O. This has no effect on the chain 12 as kthe pulleys 13, 48 are in their uppermost position. But when the operator then releases chain 38 by lifting the hook 44 at station P, it will be seen that the chains 38 and 12, as well as the members 13, 48, 50 and 10a will all be restored to their lower or initial positions.

It is frequently desired to employ only one station. In that event, if P designates such a station then the opposite end of the chain 38 is anchored to a permanent support, as at 53 in Fig. 1.

It is understood that suitable modifications may be made in the general design and structural details of the invention as herein shown, provided, however, that said modifications come within the spirit and scope of the appended claims. Having now therefore fully shownand described my invention, what I claim to be new and desire to protect by Letters Patent is:

1. A mechanism for controlling the burner of a water heating system having a tank for containin the heated water, comprising an actuator or lighting the burner a thermostatic release unit ositioned on the tank and having a strip of i-metal one end of which is rigidly anchored to the unit and the other end of which is free to move from a predetermined position when the strip bends under the action of change in temperature, a lever member carried by the release unit and releasably associated with the said free end of the bi-metal strip, and an operative connection between the lever and actuator.

2.. A mechanism for controlling the burner of a water heating system having a tank for containin the heated water, comprising an actuator or lighting the burner, a thermostatic release unit ositioned on the tank and having a stri of i-metal one end of which is rigidly anc ored to the unit and the other end of which is free to move from'a predetermined position when the strip bends under the action of change in temperature,

and a pair of interlocking levers carried by the release unit, one of said levers being releasably associated with the free end of said iii-metal strip, and'means for connecting the other lever to the valve actuator.

3. A mechanism for controlling the burner of a water heating system having aV tank for containing the heated water, comprising an actuator tor lighting the burner, a thermostatic release unit positioned on the tank and having a strip of bi-metal one end of which is rigidly anchored to the unit and the other end of which is free to move from a predetermined position when the strip bends under the action of change in temperature, and a pair ot interlocking levers carried by the release unit, one of said levers being releasably associated with the free end of said bi-metal strip, and the other lever being operatively connected to the valve actuator, and spring means tending to retain the levers in their normal interlocked positions.

4. A mechanism for controlling the burner of a Water heating system having a tank for containing the heated Water, comprising an actuator for lighting the burner, a thermostatic release unit positioned on the tank and having a strip of bi-metal one end of which is rigidly anchored to the unit and the other end of which is free to move from a predetermined position when the strip bends under the action of change in temperature, a lever member carried by the-release unit and releasahly associated with the said free end of the lui-metal strip, an operative connection between the lever and actuator, and spring means tending,y to restore the lever to operative engagement with the bi-rn'etal strip after having been released therefrom; v

The combination with a fuel valve actuator of a hot Water heating system having a tank. of a thermostatic release mechanism comprising a frame mounted on the tank, a strip ot bi-metal having one end rigidly anchored to the frame with its other end free to move from a predetermined position When the strip bends under the action of change in temperature, a latch lever carried by the frame and releasably associated with the tree end of said strip, a second lever connected with the valve actuator and pivoted to the frame for interlocking engagement with the latch lever, and means tending to retain the levers with the latch lever in engagement position with the bi-metal strip.

6. The combination with a fuel valve actuator of a hot water heating system having a tank, of a thermostatic release mechanism comprising a frame mounted on the tank, a lstrip of bi-metal having one c nd rigidly anchored to the frame with its other end free to move ,from a predetermined position when the strip bends under the action of change in temperature, a latch lever carried by the frame and releasably associated with the free end of said strip, a second lever connected with the valve actuator and pivoted to the.v 

